Size Of My Stock Muffler

Discussion in 'Touring Models' started by Webbtron, Mar 28, 2011.

  1. Webbtron

    Webbtron Banned

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    The manual didn't tell me the size of my stock 2000 RKClassic muffler, so I went to HD and all they sell are shields for 3½" muffler. But when I measure them they are 3.900" O.D. I'd like to match the same size/look when I move to a new exhaust. So are we talking 3½ I.D. or do I have 4" mufflers? Thank You Very Much
     
  2. Breeze3at

    Breeze3at Well-Known Member

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    I'm being dense, or missing something. You have heat shields on your MUFFLERS? I can only picture heat shields on the head and crossover pipes.
     
  3. Webbtron

    Webbtron Banned

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    No ....HD lists a 3½" muffler shield for my year and model. I took that as a "clue" to what I size exhaust I have. Heat shields are really the only replacement exhaust parts listed at the website.
     
  4. glider

    glider Veteran Member

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    Generally the SE mufflers on the SE bikes are the only ones that have shields on them stock.
    It should be easy enough to measure the outer diameter of the muffler being they have both 3 1/2" and 4" mufflers to be sure.
     
  5. Webbtron

    Webbtron Banned

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    Thanks Glider, I really felt it would be a O.D. measurment but wanted to be sure. I was looking at some Reinharts from a site member and thay are 3½" so now I have to think about if that ½" is going to amount to a hill of beans. Didn't have this problem with drag pipes.
     
  6. Breeze3at

    Breeze3at Well-Known Member

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    I just looked them up on the HD website. They would be a nice addition for scratched or blued mufflers. I'd never have known if you hadn't posted, Thanks.
     
  7. Webbtron

    Webbtron Banned

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    So will it matter if I step down to 3½" diameter from 4". Sounds like a large decrease of air flow, my gut says no big deal. Would that be better for back pressure?
     
  8. Breeze3at

    Breeze3at Well-Known Member

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    Outside dia. is no real indication of flow. Most aftermarket mufflers have replaceable baffles of different sizes. I have some 3 1/2"o.d. Rush's that I know have baffles available from 1 1/4" up to 2". I may be wrong, but I think the 4" o.d. is more for burly looks than performance capability.
     
  9. Webbtron

    Webbtron Banned

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    Well, now I am confused, if I buy these Rinehart pipes that are in the box do I still need baffles? All that money and it is not a working unit?
     
  10. jimharvey1

    jimharvey1 Junior Member

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    You should be OK. If you bought Rinehart slip-ons they are all together and ready to clamp & bolt on. Your inlet pipe dimension is all you need to be concerned about and if you ordered them for your stock bike with stock headpipes you should be OK. Enjoy the ride. I want a full set so bad it hurts! Just don't have a spare grand laying around looking for a place to call home right now.